A variety of products have been made using both thermoplastic and thermoset materials that include a reinforcement such as carbon fibers.
Epoxy resin materials including fillers and reinforcements, such as glass or carbon fibers, have been utilized to make a variety of structural products including composite components for automotive vehicles, boats, planes and the like. Epoxy materials with carbon fibers have also been utilized to make high pressure gas storage tanks for a variety of applications, including for use in onboard storage of hydrogen for automotive vehicles. In a variety of these applications, the polymeric materials may be subjected to static and cyclic or dynamic stresses which induce fatigue and sometimes failure of the materials for their intended application. However, epoxy resins can be brittle, and ways of toughening them without sacrificing other properties are sought. Further, the use of carbon fibers in these composite products is relatively expensive.
Wu, et al., “Structure and Properties of PBO-PEO Diblock Copolymer Modified Epoxy”, Journal of Polymer Science: Part B: Polymer Chemistry, Volume 43, 1950-1965 (2005) discloses a method of making a two-part epoxy including a block copolymer for producing vesicle, and spherical and cylindrical (worm-like) micelles. In this method, a PBO-PEO block copolymer is dissolved in acetone, and then epoxy resin and phenol novolac curing agent are added to the solution. The acetone is evaporated, and the epoxy/curing agent/block copolymer mix was cast into a plaque mold and cured. No fibers or other reinforcements were added to these plaques.
The plaques were found to have greatly enhanced toughness compared to neat resin/curing agent plaques, with little loss in other properties.